Tiny Enceladus Casts a Half-Million-Kilometre Electromagnetic Wake
A 2026 peer‑reviewed analysis of Cassini data shows Saturn’s moon Enceladus—only about 504 km across—leaving an electromagnetic Alfvén‑wing disturbance that extends at least 504,000 km downstream in Saturn’s magnetosphere, a lower bound implying a connected system linking Enceladus’s plume, the surrounding plasma torus, and Saturn’s ionosphere. The wake is an inferred electromagnetic structure rather than a literal tail, with waves, currents and reflections that broaden the moon–magnetosphere interaction; future missions could map it in three dimensions. No evidence of life is claimed.